Flight Deck Floor

Question 1

How are the brakes commanded?

Answer 1

Electrically commanded, hydraulically actuated

Question 2

What are the 4 brake control module (BCM) functions?

Answer 2

Locked wheel protection

Anti-skid

Auto brakes

Touchdown protection

Question 3

Which HYD systems control which brakes?

Answer 3

HYD 1 = Outboard brakes

HYD 2 = Inboard brakes

HYD 1+2 = Parking brake/Emergency brake

Question 4

When is locked wheel protection active?

Answer 4

On the ground > 30 KTS

Question 5

What is locked wheel protection?

Answer 5

Compares wheel speeds to keep left and right equal

Speeds 33% or less than opposite wheel, BCM commands zero pressure to slower wheel

33% chosen to allow differential braking

Question 6

When is anti-skid deactivated?

Answer 6

< 10 KTS (allows a wheel to lock for maneuvering)

When using the parking brake/emergency brakes

Question 7

When does touchdown protection allow braking?

Answer 7

Until 3 seconds after WOW

> 50 KTS wheel speed

Question 8

What does the LDG GR electrical override switch do?

Answer 8

Bypasses the PSEM and commands gear extension

Question 9

What does the Alternate Gear Extension Lever do?

Answer 9

Relieves hydraulic pressure in the lines

Releases all uplocks